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排序方式: 共有1216条查询结果,搜索用时 31 毫秒
1.
Safa Meraghni Labib Sadek Terrissa Meiling Yue Jian Ma Samir Jemei Noureddine Zerhouni 《International Journal of Hydrogen Energy》2021,46(2):2555-2564
Prognostics and health management of proton exchange membrane fuel cell (PEMFC) systems have driven increasing research attention in recent years as the durability of PEMFC stack remains as a technical barrier for its large-scale commercialization. To monitor the health state during PEMFC operation, digital twin (DT), as a smart manufacturing technique, is applied in this paper to establish an ensemble remaining useful life prediction system. A data-driven DT is constructed to integrate the physical knowledge of the system and a deep transfer learning model based on stacked denoising autoencoder is used to update the DT with online measurement. A case study with experimental PEMFC degradation data is presented where the proposed data-driven DT prognostics method has applied and reached a high prediction accuracy. Furthermore, the predicted results are proved to be less affected even with limited measurement data. 相似文献
2.
AbstractGeneralized thermoelastic interactions due to three-phase-lag time-nonlocal heat transfer in a Kelvin-Voigt type infinitely extended visco-thermoelastic continuum with cylindrical cavity has been investigated. The two-temperature generalized thermoelasticity theory has also been taken into account. The problem has been solved in the domain of Laplace on the assumption that the surface of the cavity is free from traction and is subjected to a smooth and time-dependent-heating effect. Laplace inversion of the transformed solutions has been carried out numerically. The obtained numerical data for different considerations are plotted in graphs to study the effects of time-nonlocal parameter, two-temperature parameter and visco-thermoelastic relaxation parameter on different thermoelastic quantities of physical interest. 相似文献
3.
SA Khotimchenko VM Kodentsova IA Alekseeva SG Vlaskina OA Vrzhesinskaia AA Sokol''nikov LA Kharitonchik IP Aleshko-Ozhevskií LV Sheviakova 《Canadian Metallurgical Quarterly》1997,43(3):158-164
Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells. 相似文献
4.
Conductance measurements are reported for s-alkylisothiouronium bromide, iodide and picrate salts in the dipolar aprotic solvent DMSO at 25°C. The data were analysed by Fuoss's equation (1975–1980) for 1:1 electrolytes, from which the values of Λ0, the Gurney's cosphere diameter R and KA are obtained. The results are discussed in the light of the recorded values of the constants KR and KS and the free energy term Gs. 相似文献
5.
Although thoracoabdominal injuries are uncommon in the athlete, they can be catastrophic if unrecognized or if diagnosis and treatment are delayed. This article reviews thoracic, intrathoracic, abdominal, and groin injuries in the athlete, and how they can be diagnosed and managed. 相似文献
6.
AA Bakova BD Brondz OA Fedorkina VA Gusev AI Gordienko IuS Krivoshein IuL Krivorutchenko TG Prokopenko IA Popov 《Canadian Metallurgical Quarterly》1994,39(4):187-189
The possibilities of using influenza A (Leningrad) 385/80 (H3N2) virus matrix protein-specific FITC-labeled D8 monoclonal antibodies in immunofluorescence assays were investigated. The virus antigen accumulation was detected in chorioallantoic cells of chick embryos. Exhibiting the type-specific properties, the fluorescent antibodies stain the perinuclear space, cytoplasmic membrane, and granular structures in the cytoplasm of infected cells. The haemagglutination test tires in the corresponding specimens were at least 1:16. 相似文献
7.
II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
8.
The monoclonal antibody CD 68 (KP 1) reacts with fibrohistiocytic and some epithelial neoplasms; its reactivity compared with that of HMB 45 in malignant melanoma (MM) and neural tumors needs further elucidation. Using a streptavidin-biotin-immunoperoxidase procedure, we examined the reactivity of 65 MM (46 conventional, 1 polypoid, 6 desmoplastic [DMM], and 12 metastatic), 21 neurofibromas, 1 neurofibrosarcoma, 10 schwannomas, 1 perineurioma, 2 neurothekeomas, and 14 blue and 26 other nevi for CD-68, HMB-45-defined antigen, S 100 and neurofilament protein. A positive staining for CD 68 was observed in 38 of 42 primary, 5 of 6 DMM, and 11 of 12 metastatic melanomas; 6 of 10 schwannomas; 5 of 10 nevi with junctional component and all 14 blue nevi. All 21 neurofibromas, 1 each neurofibrosarcoma and perineurioma, both neurothekeomas, and all 12 nevi with dermal component were CD 68-negative. HBM 45 was expressed by all 44 primary, none of 6 DMM, and 7 of 12 metastatic melanomas; by none of 10 schwannomas, 6 neurofibromas, 1 neurofibrosarcoma, 1 perineurioma and 2 neurothekeomas. Both junctional nevi, 8 of 10 nevi with junctional components, 1 of 10 dermal components of junctional nevi, and 11 of 13 blue nevi were also HMB 45 positive. Except for 1 perineurioma, S 100 decorated all tumors examined. NF was immunoreactive in 1 of 45 conventional melanomas, 2 of 21 neurofibromas, 2 of 10 schwannomas, and 3 of 10 blue nevi; it was non-reactive in all polypoid, desmoplastic and metastatic melanomas; neurofibrosarcoma, perineurioma, neurothekeoma and other nevi. We conclude that the CD-68-reactivity in primary melanomas, neurofibromas, neurofibrosarcomas, perineuriomas, and nevi was similar to that of HMB 45. The significantly higher CD 68-positivity than of HMB 45 in metastatic and desmoplastic melanomas and schwannomas may be of diagnostic value. 相似文献
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